Pencil sharpener



Nov. 3', 1925. 1,560,291

0. E. BORK 4 PENCIL SHARPENER Filed Aug. 8. 1925 zmyfw 2 Sheets-Sheet 1 Patented Nov. 3, 1925" UNITED STA? Es PATENT OFFICE.

O'T'IO EGON BORK, F COPENHAGEN, DENMARK.

rENcIL SHARZPENER.

Application filed August 8,1925. Serial No. 49,012.

To all who la it may concern:

Be it known that I, Or'ro Econ B01211,

. a subject of the King of Denmark, residing 'having two conical bores with oppositely arranged seatings for two cutters or knives projecting each with a sharp edge in one ofsaid bores. I

It is a well known fact, that during the use the knife edge adapted to sharpen the lead or graphite will soon be dull, due to the relatively large hardness of the graphite, and in fact it is quite impossible to procure a sharp steel edge which will not he dull in the course of very short time,

when cutting in graphite.

The purpose of the present invention. is to overcome the said drawback and the object of the invention is to form the knife or cutter, adapted to sharpen the lead or graphite, as a steel-plate, the edges of which are not sharpened, but are either plane or hollow so that the edge in question would sharpen the graphite by scraping action instead of by cutting action.

If the'said steel plate, adapted to sharpenthe graphite, is square it will have eight 'edges-four along each side face--which in succession can be employed for the scrap- 'ing purpose. Instead of being quadrangu lar the steel plate may have another polygonal shape preferably of such regular form, that any desired edge oi the said. plate may be arranged to project into the conical bore in question and thereby serve the scraping purpose.

On the drawing show:

Figure 1 an embodiment of a pencil sharpener according to the invention,

Figures 2 and 3 two diiferent side views of the pencil sharpener according to Figure 1,

Figure a an end view of the pencil sharpener, and

Figures 5 and 6 a longitudinal section and sharpener according to Figure. 1.

Figure 7 is a longitudinal sectional view of the pencil sharpener in operation, and

Figure 8 is a plan view of the pencil sharpener. t

1 isa metal or other .body. having two conical bores 2 and 3. The body 1 is in well known manner cutaway along the bore a cross-section, respectivelv, of the pencil '2 in order to form a seating for a cutter 0r knife 5, the sharp edge 6 of which pro jects into the bore 2 and is adapted to re move the wood from a pencil, the end of which is brought into the bore 2 and rotated therein. The'knifefor cutter 5 has a longitudinal slit 8 adapted to receive a screw 4 by means of which the cutter 5 is adjustably fixed to the body 1.

The bore 2 terminates in a cylindrical 'bore 7 having a relatively large diameter, 1. e., diameter, which allows the graphite or lead, or crayon of pencils of the thicknesses in question to move freely in the bore 7. lVhen unscrewing the screw 4 the cutter 5 may be moved longitudinally and thus adjusted to remove the wood of pencils of different thicknesses without scraping or cutting the graphite or lead or crayon of the 13611011 in question. In order to "avoid that the corner 20 of the cutter 5 will cut or scrape the graphite orcra'yon,

the said corner may be convex instead of being concave as shown.

The graphite or-crayon of the pencil is subsequently sharpened by insertion of the end of the pencil, from which the wood hasbeen removed by means of the cutter 5, into the conical bore 3, which similarly to the bore 2 terminates into a short cylindrical bore 9, which, however, has a considerably smaller diameter than the bore 7. The body 1 has near the bore 9 a recess 19, Figures 3 and 6, which communicates with the bore 3 or 9 and forms a seating for a cutter or scraper 10, which. in the embodiment shown is a quadrangular plate, the circumscribingfaces of which are either fiat and perpendicular to the side faces of the plate, or hollow so that the edges of the plate will not form knife edges, but scraping edges.

The plate 10 is preferably arranged at a suitable angle relatively to the side face of the body 1, so that one of the edges of the m u t d in, S d utaw Pa n h plate 10, i. e., the edge 11 in Figures 5 and 6 is located in the bore'3or' 9. The said edge 11 would effect a scraping action on the graphite or crayon of the pencil,'when the end of the latter is inserted in the bore 3 and rotated.

The plate or scraper 10 is fixed'tothe body 1 by means of a screw The plate 10 may be turned about the axis of'this screw, when the latter is unscrewed, and thus anyone of the edges of the plate 10 may be caused to project into the bore 3 or 9. If th e'screw'13 is re no ved, the plate 10 may be turned over, so'that the underside of the plate 10 in Figure 6 may be turned upwardly and the edge along saine applied for the scraping effect. Thus a quadrangular platelO will have eight applicable scraping edges. "I 7 Instead of bcing'quadrangula r the plate 10 my hate any other polygonal shape and will then present 'a correspondingly larger or smaller number or scraping edges.

The shape of the'body' land tllQlJOSltions of the bores 2 and B'relatively' to one another do not form parts of the invention, but may be aried in any desired manner. i i i 1 Thus the two bores 2 and may be arranged in prolongation of'one another to torn; together a singl efborc, asshown in Figures 7 and 8. The scraper and the cutter 5 are, by this einbodinient oft-he invention, ar anged to project both in aid bore in such a nanner that the scrapers lQ will a scraping, action on the lead: 30 of the pencil 4:0, simultaneously with the rein oral of the wood from the adjacent part of the pencil byineans or the cutter 5. Haring Enorv particularly described and ascertained the natureof my said inyentlon and in What manner the same is to be per formed, I declare what I claim is 1 A pencil sharpener, 'coinprisiiig a body part with a conical bore artist, and a cutaway part forming a longitudinal opening into the conical bore, akni fe-ed'ge cutter i s u ti d innit-d ne lei g fii l 'w l in? to the conical bore, a; scraper mounted on the body part and adapted to sharpen the lead ofthe pencil only, the said scraper consisting of a polygonal plate arranged to be turned in the plane of its support on the body part in order that any one of itscircuinferential edges may be brought in posit'ion to project into the conical bore in the body part to exert a scraping action on the lead or the pencil or crayon.

2. A pencil sharpener, comprising a body part with a conical bore therein, and a cutaway part forming a longitudinal opening into the conical bore, a knifeedge cutter n ountd in said c'ut-away p art and having 11 u t ng-ed e PFQJQQ ng ngitudleally rd the conical bore, and 'a scra er mounted on the body partandadaptecto sharpen the lead of the pencil only, the said scraper consisting of a pol gonal plate iy'itl i. rectangular scraping ec ges, theplate being rotatably mounted 911 thebody' part "and capable of being turned in theplane of its support in order that any one of its cir cuinferential edges n ay be brought in position to'pro'j'ect into the conical bore in the body part and to erert a scraping action on the lead of the pencil or crayon, V

A pencil sharpener comprising a body part with two conical recesses therein, a cutaway part toriniing longitudinal opening into one'ol the conical recesses, a knifee'dge cutter inountediii said'cut-away part, and arranged to project with its cutting edge longitudinally into the recess, and a scraper mounted upon the bodypart and adjacent one end of the second conical recess, the scraperbeing adapted to sharpen the lead of the pencil-only, the said scraper consisting of a polygonal plate with rectangular scraping edges, the plate bei-ng mounted on the body part and rotatably mounted tobe, turned in 'the'plane of its support in girder; that any one of its circumferential edges may be brought in position to project into the second conical recess to exert a scraping action on the lead of the pencil or crayon' f lnftestiinony whereof he hereunto allixes his signature i it OTTO EGON BORIQ 

